You are here: Home - Position encoders - Laser encoders - RLE fibre optic laser encoder - Differential interferometer

Differential interferometer

The Renishaw differential interferometer detector head allows measurement of the relative displacement between a fixed, reference mirror, and a moving measurement mirror.

Page contentDownloadsCall your local office Contact us online

The RLD10-X3-DI detector head has been designed to mount to the external wall of a process chamber via a simple three-pin mount. There is no need to enter the chamber to align the detector head - integral beam steerers allow independent pitch and yaw adjustment of reference and measurement beam - and the design of the mounting system allows the detector head to be removed and repositioned with minimal effect on system alignment.

The DI detector head is often specified as part of an RLE20 system; the high resolution RLU20 laser source being ideally suited to measurements in vacuum chambers and other strictly controlled environments.

Specification

Range  0 m - 1 m
Cyclic error <1 nm
Output signal format Digital - RS422 quadrature
Analogue - 1 Vpp sine / cosine
Maximum velocity 1 m/s
Laser type HeNe (Helium / Neon), 632.8 nm, Class II
Laser lifetime >50,000 hours

Figures are based on using the RLD10-X3-DI head with an RLU20 laser unit

Features and benefits

  • Exceptional metrology
    ppb frequency stability and ultra low cyclic error, allowing output resolutions to 38.6 pm.
  • Differential configuration
    Measures the relative position of stage versus column, or workpiece versus tool, and eliminates common mode errors such as motion of the chamber sidewall associated with environmental fluctuations.
  • Rapid alignment
    Simple alignment from outside the process chamber using four integrated beam steerers (±1° pitch and yaw adjustment for both measurement and reference beams) to overcome chamber and mirror mounting tolerances.

Documents

  • High precision laser interferometer feedback systems brochure High precision laser interferometer feedback systems brochure

    Brochure provides details on the range of Renishaw laser interferometer based encoders and related systems.

    [8.4MB]
  • Data sheet: RLE system performance Data sheet: RLE system performance

    Data sheet describes the RLE system which provides the positioning performance expected from an interferometer, with ease of installation and use.

    [1.6MB]
  • Data sheet: RLD10 DI (differential interferometer) detector head Data sheet: RLD10 DI (differential interferometer) detector head

    This data sheet describes the RLD10-X3-DI differential interferometer detector head, which measures the relative displacement between a fixed, reference mirror, and a moving measurement mirror.

    [395kB]
  • RLD10 DI news release RLD10 DI news release

    New, differential measurement configuration provides a fibre optic launched interferometer solution for precision motion control in vacuum or other controlled environments.

    [31kB]
  • News article: RLE20 interferometer enhances performance of Vistec Lithography’s latest e-beam tool News article: RLE20 interferometer enhances performance of Vistec Lithography’s latest e-beam tool

    Vistec Lithography’s (previously Leica Microsystems) VB300 e-beam lithography tool is a development of the highly successful VB6 series introduced in 1993. In designing the new tool, Vistec identified that a reduction of noise-induced positional errors would significantly improve tool performance. Through a combination of improved mechanical rigidity and integration of the Renishaw RLE20 differential interferometer based encoder system, these errors are now expected to be <3 nm.

    [2.4MB]

Next steps

Contact us online if you require more information or you have a pricing query, or alternatively you may like to speak directly to your local Renishaw office.